Vacuum coffee brewer



. notarse VACUUM corran: nnen Harvey @ormhicagm mi. appresa@ May as, 193s, sei-iai No. @2,222

3 Claims.

This inventionrelates generally toa coee brewing utensil of the vacuum type, 'in whichis included two vessels, one a decanter and the othe'rra funnel, the latter having a tubular stem depending into the decanter for sealed connection therewith. More particularly, the present improvements are directed to a filtering unit disposed within the funnel adjacent yits base forv ystraining fluid passing between the funnel and the decanter. v

It is an object of my invention to devise for the purposes noted a filter devicewhich is simple in the extreme, yinexpensive to produce,l easy to clean, and `otherwise readily adaptable to meet the needs of a vacuum coffee brewer. My irnproved filter, together with the. holder or mountments have to do with the strainer element and its cooperation with the holder or mounting therefor, and with the cooperating funnel seat with which it engages. f

A'li'hese and other objects of my invention are realized by the construction which is herein shown and described; a. suggestive embodiment whereof is illustrated in the accompanying drawingwhere- 1n Figure 1 is a central longitudinal section through a vacuum coffee brewer showing inelevation the lter unit in operative position;

Fig. 2 is a view in perspective of the filter unit per se;

Fig. 3 is scale, taken on line 3 of Fig. 1; and

Figs. t and 5 are details in section, taken, respectively, on lines t and t of Fig. 3.

The codec brewer illustrated which is of the vacuum type comprises a decanter D adapted to be rested upon or over a heater (not shown). Fitted within the necks of the decanteris a bushing it through which is extended a tubular stem li depending from a funnel F. A handle (not shown) may be connected to thel neck of the decanter, as is usual.

The funnel stem which is open at its lower end extends downwardly into the decanter close to the bottom thereof. At its upper end the stem rounds outwardly as at i2 to provide a seat which joins with the base i3 of- 'the funnel which, las

a detail in section, on an enlarged l shown, may be in the general form of a cupshaped bowl. It will be understoodthat the decanter may be made of heat-proof glass in one piece, and that the funnel with its 'depending stem may also be produced in the same way of like material.

'I'he lter unit shown separately in Fig. 2 comprises a bar B, deslrably of heat-proof glass, having, by preference, a slight taper from each end toward its middle upper region where it is outwardly swelled to provide a generally spherical body or ball i5. At its upper end the bar may be equipped with ahead l'l. The ball is adapted to engage with and rest upon the seat of the funnel where it establishes a circular line contact therewith. I provide around the ball, in the region of its circular line of contactga plurality of short grooves 2t extending in planes which are radial to the axis of the bar, as best shown in Fig. 3. These grooves which are preferably in adjacent relation are generally angular in form so as to provide narrow ribs p with intervening recesses 1'. It is the ribs alone which are enabled to make Contact with the seat of the funnel; the recesses, however, afford `narrow passages through which communication is maintained between the decanter and funnel.

As part of the filter unit I provide a' strainer washer W adapted to be fitted upon the bar in a position y'adjacent the ball. This washer is desirably produced from a single thickness of fabric by a blanking operation, and when'inloperative position will surround the grooves v2t therein. In practice, the washer will rest upon the funnel Aseat to separate the ball therefrom along the c'ircular line of contact just referred to. The fabric material of whichV the washer is made will be compressed opposite each of the ribs p, but elsewhere, opposite in the recesses r, will be loose and unconfined.

-In operation, water is placed in the decanter,v

heating the water in thejdecanter, a pressure of air or steam is developed which is directed against the strainer element.` In response to this pressure which is followed by upiiow of water, .the strainer will permit the water to pass upwardly through the recesses r into the funnel to produce `an infusion. When substantially all the water l in the decanter has passed into the funnel, the

heat is shut oil. With consequent cooling of the decanter a vacuum or minus pressure is produced which draws the infusion back from the funnel. In this return or downfiow, the infusion is required to pass through the strainer before entering the decanter. During this stage of the operation, the strainer, opposite the ribs p, is compressed tightly upon the illter seat so as to substantially close the openings at such points against the passage of liquid. Between these ribs, however, i. e., within the recesses, the washer fabric is loose and free to expand so as to function after the manner of a wick to permit free seepage oi' the infusion' therethrough. 'Ihrough such portions of thewasher-strainer as are unconilned and free of pressure, the liquid will pass. but without permitting grounds or other particles to go through.

The surfaces of the ball and seat may be convex, as shown, sothatthe contact therebetweenl is in the form of a circular line. This line, however, is broken by the series of ribs which define spaced points of engagement. Accordingly the circular line of contact is broken into a number of closely spaced points arranged circularly about the seat. It is at these points only that the strainer is compressed. Elsewhere, bothv above, below and between the points of contact, the strainer is relatively unconilned and so may swell in the presence of liquid topromote a capillary drainage therethrough. By reason of the pointcontact relationship described, the efllciency of the strainer is enhanced sc that there will be a minimum of resistance to the flow of liquid from which all particles, grounds, etc., are separated during passage of the coiee infusion downwardly into the decanter.

'Ihe resulting brew is what may be termed a true coilee infusion in that it is not contaminated with derivatives of metals or other materials which are wholly absent from inside the decanter and funnel. The brew is crystal clear and distinctly superior in avor.

I claim:

l. In a vacuum coee brewer, the combination of two communicating vessels in sealed connection, there being a circular line seat in the line of communication therebetween. and a illter unit adapted to rest upon the seat. the filter unit comcesses, the ribs being so disposed as to engage the circular line seat, and a flexible strainer in the form o1 a washer tted upon the bar and against the ball to rest upon the seat and receive contact only in a circular line from the ribs oi' the ball whereby the strainer material between the ribs and on opposite sides of the circular line is loose and free to swell for promoting capillary drain-`A age of liquid therethrough.

2. Ina vacuum coil'ee brewer, the combination of two communicating vessels in sealed connection, there being a seat in the line of communication therebetween, and a lter unit adapted to rest upon the seat, the illter unit comprising a ball having a series of closely spaced parallel ribs arranged in planes radially oi' the line oi communication axis and defining between them intervening recesses. the ribs being positioned to engage the seat, and a flexible strainer -interposed between the ball and seat and receiving pressure from the ribs alone whereby the strainer material vin the-intervening recesses is loose and free to swell for promoting capillary drainage of liquid therethrough.

3. In aA vaccum coffee bre er," the combination of two communicating vessels in sealed connection, there being a circular convex seat in the line of communication therebetweemand a illter unit adapted to rest upon the seat. the filter unit being formed with a convex surface having a series of closely spaced parallelv ribs arranged in planes radially of the line of communication axis and deilning between them intervening recesses, the 

